Corner control system for plaster walls

ABSTRACT

An expansion joint system for corners of plastered walls comprising a pair of angularly related and allochirally arranged casing beads extending longitudinally along and defining such a corner, the casing beads providing outwardly extending first flange portions terminating in close adjacency to define a corner seam and a corner space. A longitudinally extending connector member having an L-shaped cross section is disposed within the corner space defined by the first flange portions, this member having a longitudinally extending apex and inwardly and longitudinally extending leg sections, one of the leg sections abutting each first flange portion and the apex being disposed in close adjacency to the seam. Each casing bead also provides a clip portion positioned and arranged to engage and hold the adjacent leg section against its said first flange portion.

ate 1.

United States Bentle CORNER CONTROL SYSTEM FOR PLASTER WALLS [76] Inventor: Ralph W. Bentle, 1326 N. Audubon Rd., Indianapolis, Ind. 46219 [22] Filed: July 8, 1971 [21] Appl. No.: 160,739

[11] dflfifidd Oct. 16, 1973 5 7] ABSTRACT An expansion joint system for corners of plastered walls comprising a pair of angularly related and allochirally arranged casing beads extending longitudinally along and defining such a corner, the casing g l i d beads providing outwardly extending first flange por- 58 Field of Search ..52/254-257, clse adjacency define a seam and a corner space. A longitudinally extending connector member having an L-shaped cross section is disposed within the corner space defined by the first flange portions, this member having a longitudinally [56] References cued extending apex and inwardly and longitudinally ex- UNITED STATES PATENTS tending leg sections, one of the leg sections abutting 1,297,906 3/1919 Quass 287/20.92 W each first flange portion and the apex being disposed 3,608,260 9/197] Eckel et aL... 52/588 in close adjacency to the seam. Each casing bead also provides a portion positioned and arranged to en 2,151,605 3/1939 Lavermg 52/254 g g and hold the adjacent l Section against i Said 2,904,992 9/1959 Cruser 52/573 first flange portion 3,559,356 2/1971 Koral 52/254 12 Claims, 7 Drawing Figures CORNER CONTROL SYSTEM FOR PLASTER WALLS The present invention is in the field of plastered walls and more particularly relates to providing expansion joints or corner control systems for intersecting plastered walls and ceilings. It is well known that plastered walls and ceilings develop cracks which start at the intersections of side walls and/or at the intersections of ceilings and side walls. These cracks or separations are usually caused by expansion and contraction or settling of the building. I

Several types of easing beads and expansion joint systems for plastered walls have heretofore been suggested. Representative systems are disclosed in US. Pat. Nos. 2,234,701; 2,904,922; and 3,398,494. My present invention provides an improvement over the prior art systems as will be discussed hereinafter.

conventionally, casing beads have been used to define corners. Casing beads are elongated, strip-like sheet metal devices which may be fastened to plaster bases such as metal lath, styrofoam, masonry, gypsum lath, and the like. Generally, a corner is defined by a pair of angularly related, allochirally arranged casing beads, outwardly extending flange portions of which meet to define a corner seam. As will be discussed hereinafter, I provide a connector member having an L-shaped cross section including a longitudinally ex tending apex and inwardly and longitudinally extending leg sections. This connector member, with its inwardly extending leg sections, fits in the corner space bounded by the seam defining flange portions of the casing beads and the intersecting plaster bases. Each casing bead provides a clip portion which engages the adjacent leg section of a connector member and resiliently urges it against the flange portion of the casing bead. It will be appreciated that each leg section extends inwardly and perpendicularly to the wall on which its associated casing bead is mounted. Thus, since the leg sections are resiliently held for slippage, the walls can move without developing an unsightly crack or open joint.

Other objects and features of my present invention will become apparent as this description progresses.

To the accomplishment of the above and related objects, my invention may be embodied in the forms illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that change may be made in the specific constructions illustrated and described, so long as the scope of the appended claims is not violated.

IN THE DRAWINGS FIG. I is a fragmentary, exploded perspective view of a corner control system constructed in accordance with my present invention; I

FIG. 2 is a fragmentary sectional view of a corner taken along line 2-2 in FIG. 1 and FIG. 2a is an enlargement of a portion of FIG. 2;

FIG. 3 is a fragmentary sectional view showing a similar comer control system with the casing beads integrally formed to provide the clip portions as well as the flange portions which define the corner;

FIG. 4 is a fragmentary sectional view showing a corner control system similar to the system of FIG. 1 except that a modified form of clip is used;

FIG. 5 is a corner control system similar to that of FIG. 3 except that the casing beads are attached to the back surfaces or inner surfaces of the intersecting plaster bases; and

FIG. 6 is a fragmentary sectional view of a corner control system similar to the system of FIG. 1 except that another modified form of spring clip is used.

In this description, and in the claims appended hereto, the terms corner" or corners are intended to mean the intersections of side walls as well as the intersections of ceilings and side walls. Further, the term longitudinally is intended to mean the direction of the line defined by the intersecting side walls or ceilings and side walls.

Referring now to the drawings, and particularly to FIGS. 1, 2 and 2a, it will be seen that I have shown intersecting side walls I0, 12 and ceiling 14, the side walls 10 and 12 being defined by plaster bases 16, 18 and the ceiling being defined by plaster base 20. In FIG. 1, I show casing beads 22, 24, 26, 28, 30 and 32, the casing beads 22 and 24 defining the corner between the walls 10 and 12 with the casing beads 26, 28 and 30, 32 defining thecorners between the ceiling l4 and the walls 10 and 12.

As illustrated, each casing bead 22-32 may include an expanded metal portion 34 which lies against the associated plaster base 16, 18, 20. Casing beads are conventionally provided with such expanded metal portions.

The casing beads 22-32 are identical and a description of one such casing bead herein will suffice. Further, as clearly shown in FIG. 2, the casing beads 22, 24, are angularly related, i.e., at right angles, and allochirally arranged to define the interior corner of the plastered walls. Referring particularly to FIGS. 2 and 2a, it will be seen that each casing bead 22, 24 includes an outwardly and longitudinally extending first flange portion 38 terminating with a longitudinally extending first edge 40 and Ya second longitudinal flange portion 42 extending away from the first edge 40 and such a corner. Each second flange 42 terminates with a longitudinally extending second edge 44. Each casing bead 22, 24 also includes a third longitudinal flange portion 46 extending away from the inner edge of the first flange portion 38 and the corner and parallel to the said second flange portion 42. The expanded metal portion 34 may be attached to this third flange portion 46 or the distal edge portion of the third flange portion may be expanded by conventional processes to provide the portion 34. It is this third flange portion 46 which is usually nailed, bradded, orotherwise securely fastened to the plaster base l6, 18.

The casing beads 22, 24 described thus far are conventional and are presently used to define corners of plastered walls. The flange portions 42 serve as reference flanges to determine the depth of the plaster as applied to the plaster bases 16, 18. In the trade, the flange portions 42 are said to provide a ground to control the thickness of the plaster.

The first flange portions 38 (FIG. 2) are at right angles to each other with their first edges 40 disposed in close adjacency or contacting to define a corner seam or joint as indicated at 50 and an interior corner space 52 bounded by the flange portions 38 and the plaster bases l6, 18. The plaster 54 of course may be applied in any conventional manner to the plaster bases l6, 18.

If the plaster bases 16, 18 separate, for instance, because of contraction or expansion or settling, the two edges 40 of the first flange portions 38 will separate to leave an unsightly crack or opening extending longitudinally along the corner. In order to remedy this situation, I provide an elongated connector member 60 having an L-shaped cross section providing a longitudinally extending apex 62 and longitudinally and inwardly extending leg sections 64, 66. This connector member is disposed in the corner space defined by the first flange portions 38 with the inwardly extending leg sections 64, 66 abutting the outwardly extending first flange portions and the apex 62 being disposed in close adjacency to the adjacent first edges 40, i.e., to the seam 50. Then, as will be more clearly described hereinafter, each casing bead includes a clip portion positioned and arranged to engage and hold the adjacent leg section 62, 64 against the first flange portion 38 of the casing bead. As clearly seen in FIG. 2, if either wall 10, 12 moves away from the other wall, the apex portion of the connector member will fill the space between the edges 40 to prevent an unsightly crack or opening from appearing In the embodiment of FIGS. 1, 2 and 2a, the leg sections 64, 66 of the connector member 60 are held against the first flange portions 38 by a longitudinally extending clip member including an outwardly extending resilient spring arranged to urge the adjacent leg section against its associated first flange portion 38. The illustrative clip member includes a flange 70 which may be attached to the third flange portion 46 by spot welding, riveting or other such fastening techniques, and an outwardly extending flange 72 reversely bent as indicated at 73 to provide an inwardly and longitudinally extending tab 74 for engaging the adjacent leg section 66. The flange 72, which is the said spring in this embodiment, is bent at a radius 73 such that it provides a longitudinally extending curved surface contacting the adjacent leg section along a contact line indicated at 76 (FIG. 2a). This curved surface facilitates the entry of the leg section into the space between the clip member and the first flange portion 38. As clearly shown in FIG. 2a, this line of contact 76 is closer to the outer edge portion of the leg section 66 than it is to the inner edge portion of the leg section.

Referring now to FIG. 6, it will be seen that the clip member illustrated therein includes a flange portion 78 securely fastened to the third flange portion 46, an outwardly extending spring portion 80 reversely bent at its distal edge to provide a diagonally inwardly extending tab 82. The spring portion 80 extends outwardly and slightly toward the adjacent first flange portion 38 to engage and urge the adjacent leg section 64, 66 against that first flange portion. Each such spring portion 80 contacts its associated leg sections 64, 66 in the region adjacent the bend which provides the tab 82.

Referring to FIG. 4, it will be seen that each clip member includes flange portions 90, 92, 94, 96 with the flange portion 90 being fastened to the third flange portion 46. The clip members illustrated in FIG. 4 are formed in the manner illustrated to provide a greater spring force for urging the leg sections 64, 66 against their respective first flange portions 38. Particularly, the bends between the portions 90, 92 and 92, 94 and the angles between these portions provide greater strength than is provided by a generally flat flange which extends generally outwardly and slightly toward the adjacent first flange portion 38.

Referring now to FIGS. 3 and 5, it will be seen that I have illustrated casing beads which are integrally fonned from an elongated sheet metal strip such that the clip portion or clip member is an integral part of the rest of the casing bead. Each casing bead is, therefore, an elongated sheet metal strip formed at one edge portion to provide the first flange portion 38, at its intermediate portion to provide a reversely bent spring portion 102 (FIG. 3), 102' (FIG. 5) extending outwardly and slightly toward the first flange portion 38 to serve as the clip portion, and at its opposite edge portion to provide a mounting flange strip (third flange portion 46) extending away from the corner and the inner edge of the first flange portion 38. The distal edge of the said one edge portion is bent at a right angle to extend away from the seam between the edges 40 and parallel to the mounting flange strip 46 to provide the said second flange portion 42.

It will be appreciated that the difference between the casing beads of FIGS. 3 and 5 involve the depth of the first flange portions 38 and the spring portions 102, 102'. In the structure of FIG. 3, the third flange portions 46 are mounted on the outer sides of the plaster bases 16, 18 while in the FIG. 5 structure these flange portions 46 are mounted on the inner surfaces of the plaster bases 16, 18.

The system shown in FIGS. 1, 2 and 20 has been successfully used in a construction project and found to be very advantageous. In that system, standard and commercially available 15 inch casing beads 22, 24 were modified by adding the described clip portions thereto. Particularly, the clip members provided by the flanges 70, 72, 74 were spot welded to the third flange portions 46. Then, the cooperating casing beads 22, 24 were joined together by use of connector members 60, each leg section 64, 66 of which had a depth 9% inch less than the depth of the casing beads. The flanges 72 were reversely bent such that the clip members extended outwardly approximately 1% inch less than the depth of the casing beads.

In the installation, the cooperating casing beads 22, 24 previously joined together by a connector member 60 were mounted as a corner assembly at the intersections of side walls and at the intersections of ceilings with side walls. The assemblies were conventionally fastened to the plaster bases. The assemblies were trimmed as illustrated in FIG. 1 such that three such assemblies could intersect and mate together at the three dimensional corner juncture defined by the intersection of the ceiling and side walls.

Before the jointed cooperating casing beads 22, 24 are attached to intersecting plaster bases, relative longitudinal slippage of the casing beads or lateral separation of the casing beads may be prevented by placing a piece of adhesive tape about the backs of the casing beads. Such tape, which can be left on the installed casing beads, will facilitate holding the beads together during the process of cutting them to length or cutting them to fit in a corner as shown in FIG. 1.

It has been found that my present corner control system results in great savings in both construction cost as well as in the total amount of construction project time allotted to the plastering effort. The cost saving is achieved because the plastering craftsmen spend significantly less time and the project time saving is achieved because the exterior walls, partition walls and ceilings of a room may be plastered in one operation.

Using conventional and commercially available casing beads which are conventionally set against a previously plastered and whitecoated wall or ceiling to define a corner, the present industry practice for completing a room is a three-step practice. Step 1 involves preparing a plaster base on the exterior wall of the room and then plastering the exterior wall including applying the white coat. Step 2 involves setting the studs and preparing a plaster base on the partition walls and then plastering the partition walls including applying the white coat. Step 3 then involves hanging ceiling support channel and preparing a ceiling plaster base and then plastering the ceiling including the white coat. Since it is conventional to place a casing bead against a wall which has already been white coated, all of the walls and ceiling of a room are not simultaneously plastered.

My corner control system utilizing the assembled casing beads, i.e., casing beads connected together by L- shaped connector member, permits use of two steps. Step 1 involves preparing the plaster base, i.e., lath or the like, on the exterior walls, ceiling and partition walls and then mounting the assembled casing beads in all the corners. Step 2 then involves plastering the exterior walls, partition walls and ceiling including the white coats. If scaffolding is required, using my system and'the described two-step approach, it is necessary only to assemble and disassemble the scaffolding one time.

The said second flanges 42 have a width of approximately inch conventionally. Thus, each corner is conventionally defined by right angle flanges 42 extending outwardly from the corner approximately A inch. My L-shaped connector member with the leg sections 64, 66 extending perpendicularly inwardly toward the plaster bases l6, l8 and with the connector member disposed in the corner space defined by the first flange portions 38 provides means for closing the crank or opening between the edges 40 without requiring ad ditional flange portion 42 width. With my corner control system, the plaster 54 approaches as close to the corner as it does with conventional casing beads. This is a very significant and important point with respect to fire ratings.

What is claimed is:

1. Expansion joint structurefor plastered walls, said structure comprising walls intersecting at right angles to define an interior comer, a pair of elongated cooperating casing beads extending longitudinally along said comer and attached to said walls, one of said casing beads extending away from said comer against each said wall, each of said casing beads providing an outwardly and longitudinally extending first flange portion terminating with a longitudinally extending first edge and a second longitudinal flange portion extending away from said first edge and said corner, each second flange portion terminating with a longitudinally extending second edge, said first edges being disposed in close adjacency to define a comer seam, a longitudinally extending connector member having an L-shaped cross section conformingly disposed in the space defined by said first flange portions, said connector member having a longitudinally extending apex and inwardly and v I longitudinally extending leg sections, one of said leg sections abutting each said first flange portion and said apex being disposed in close adjacency to said first edges, and each of said casing beads also providing a longitudinally extending spring-like clip portion positioned and arranged to engage and hold the adjacent leg section against its said first flange portion.

2. The structure of claim l in which each casing bead is formed to provide a third longitudinal flange portion extending away from the inner edge of said first flange portion and such a corner and parallel to said second flange portion, and in which said clip portion includes a longitudinally extending clip member fastened to the inner surface of said third flange portion, said clip member including an outwardly extending resilient spring arranged to urge the adjacent leg section against its associated first flange portion.

3. The structure of claim 2 in which each outwardly extending resilient spring is reversely bent at its distal edge to provide a longitudinal tab extending diagonally inwardly toward such a corner.

4. The structure of claim 2 in which each said outwardly extending resilient spring is reversely bent to provide an inwardly and longitudinally extending tab for engaging the adjacent leg section.

5. The structure of claim 4 in which said spring is reversely bent at a radius to provide a longitudinally extending curved surface contacting said leg section along a contact line.

6. The structure of claim 5 in which said contact line is closer to the outer edge portion of said leg section than it is to the inner edge portion of said leg section.

7. The structure of claim 1 in which said clip portion includes a longitudinally extending clip member arranged to urge the adjacent leg section against its associated first flange portion, said clip member including a spring extending outwardly and, in its free state, toward said first flange portion to engage said leg section.

8. The structure of claim 7 in which said spring is bent at a radius adjacent its distal edge to provide a longitudinal tab extending diagonally inwardly toward such a corner, said radius providing a longitudinally extending curved surface contacting said leg section along a contact line.

9. An expansion joint structure for plastered walls comprising walls intersecting at right angles to define an interior corner, a pair of angularly related and allochirally arranged casing beads extending longitudinally along and defining a seam for said corner, said casing beads being attached to said walls, said casing beads providing outwardly extending first flange portions terminating in close adjacency to define said corner seam and a comer space between said first flange portions and said intersecting walls, and a longitudinally extending connector member having an L-shaped cross section disposed within the corner space defined by said first flange portions, said member having a longitudinally extending apex and inwardly and longitudinally extending leg sections, one of said leg sections abutting each said first flange portion and said apex being disposed in close adjacency to said seam, and each casing bead also providing a spring-like clip portion positioned and arranged to engage and hold the adjacent leg section against its said first flange portion.

10. The structure of claim 9 in which said clip portion includes a longitudinally and outwardly extending spring clip engaging and urging the adjacent leg section against its associated first flange portion.

ill. The structure of claim 9 in which each said casing bead includes an elongated sheet metal strip formed at one edge portion to provide said first flange portion, at its intermediate portion to provide a reversely bent spring portion extending outwardly and toward said first flange portion to serve as said clip portion and at its opposite edge portion to provide a mounting flange of said one edge portion is bent at a right angle to exstrip extending away from such a corner and the inner tend away from such a seam and parallel to said mountedge of said first flange portion. ing flange strip.

12. The structure of claim 11 in which the distal edge 

1. Expansion joint structure for plastered walls, said structure comprising walls intersecting at right angles to define an interior corner, a pair of elongated cooperating casing beads extending longitudinally along said corner and attached to said walls, one of said casing beads extending away from said corner against each said wall, each of said casing beads providing an outwardly and longitudinally extending first flange portion terminating with a longitudinally extending first edge and a second longitudinal flange portion extending away from said first edge and said corner, each second flange portion terminating with a longitudinally extending second edge, said first edges being disposed in close adjacency to define a corner seam, a longitudinally extending connector member having an L-shaped cross section conformingly disposed in the space defined by said first flange portions, said connector member having a longitudinally extending apex and inwardly and longitudinally extending leg sections, one of said leg sections abutting each said first flange portion and said apex being disposed in close adjacency to said first edges, and each of said casing beads also providing a longitudinally extending spring-like clip portion positioned and arranged to engage and hold the adjacent leg section against its said first flange portion.
 2. The structure of claim 1 in which each casing bead is formed to provide a third longitudinal flange portion extending away from the inner edge of said first flange portion and such a corner and parallel to said second flange portion, and in which said clip portion includes a longitudinally extending clip member fastened to the inner surface of said third flange portion, said clip member including an outwardly extending resilient spring arranged to urge the adjacent leg section against its associated first flange portion.
 3. The structure of claim 2 in which each outwardly extending resilient spring is reversely bent at its distal edge to provide a longitudinal tab extending diagonally inwardly toward such a corner.
 4. The structure of claim 2 in which each said outwardly extending resilient spring is reversely bent to provide an inwardly and longitudinally extending tab for engaging the adjacent leg secTion.
 5. The structure of claim 4 in which said spring is reversely bent at a radius to provide a longitudinally extending curved surface contacting said leg section along a contact line.
 6. The structure of claim 5 in which said contact line is closer to the outer edge portion of said leg section than it is to the inner edge portion of said leg section.
 7. The structure of claim 1 in which said clip portion includes a longitudinally extending clip member arranged to urge the adjacent leg section against its associated first flange portion, said clip member including a spring extending outwardly and, in its free state, toward said first flange portion to engage said leg section.
 8. The structure of claim 7 in which said spring is bent at a radius adjacent its distal edge to provide a longitudinal tab extending diagonally inwardly toward such a corner, said radius providing a longitudinally extending curved surface contacting said leg section along a contact line.
 9. An expansion joint structure for plastered walls comprising walls intersecting at right angles to define an interior corner, a pair of angularly related and allochirally arranged casing beads extending longitudinally along and defining a seam for said corner, said casing beads being attached to said walls, said casing beads providing outwardly extending first flange portions terminating in close adjacency to define said corner seam and a corner space between said first flange portions and said intersecting walls, and a longitudinally extending connector member having an L-shaped cross section disposed within the corner space defined by said first flange portions, said member having a longitudinally extending apex and inwardly and longitudinally extending leg sections, one of said leg sections abutting each said first flange portion and said apex being disposed in close adjacency to said seam, and each casing bead also providing a spring-like clip portion positioned and arranged to engage and hold the adjacent leg section against its said first flange portion.
 10. The structure of claim 9 in which said clip portion includes a longitudinally and outwardly extending spring clip engaging and urging the adjacent leg section against its associated first flange portion.
 11. The structure of claim 9 in which each said casing bead includes an elongated sheet metal strip formed at one edge portion to provide said first flange portion, at its intermediate portion to provide a reversely bent spring portion extending outwardly and toward said first flange portion to serve as said clip portion and at its opposite edge portion to provide a mounting flange strip extending away from such a corner and the inner edge of said first flange portion.
 12. The structure of claim 11 in which the distal edge of said one edge portion is bent at a right angle to extend away from such a seam and parallel to said mounting flange strip. 